JSFiddle - React, Tailwind, and code Playground

JavaScript

function empty(str){
        return !str || !/[^\s]+/.test(str);
    }

    console.log(empty(null)); // true
    console.log(empty(0)); // true
    console.log(empty(7)); // false
    console.log(empty("")); // true
    console.log(empty("0")); // false
    console.log(empty("  ")); // true